Rollers mountable to a cooling bed plate transfer grid

ABSTRACT

An inexpensive, high capacity, and easy to install roller ( 20 ) for engaging hot metal plates being transferred over a cooling bed plate transfer grid. An invertible block which may have a bearing is provided at each end of the axle ( 22 ) for the roller. The bearing block ( 24 ) is received in a cut-out in the upper edge of a respective elongate parallel grid member. The bearing block ( 24 ) is clamped in the cut-out by a plate which is received in a pair of slots in forward and aft edges of the cut-out to clampingly overlie the bearing block ( 24 ).

This is a continuation of application Ser. No. 09/610,649 filed on Jun.30, 2000 now abandoned.

The present invention relates generally to transfer grids for coolingwhile transferring hot ferrous and non-ferrous metal plates formed in aplate mill and the like. More particularly, the present inventionrelates to rollers mounted thereto to engage the plates beingtransferred so that friction between the plates and the grid is avoidedor reduced.

My prior U.S. Pat. Nos. 5,265,711 and 5,301,785, which are herebyincorporated herein by reference, disclose the clamping of rollersupporting inserts in transfer grid pockets for moving of the platesover the rollers. The roller is rotatably mounted by means of a bushingon an axle the ends of which are secured in apertures in plates. Membersforward and aft of the roller and sandwiched between and welded to theplates form a frame in which the roller is mounted. See also my priorU.S. Pat. Nos. 5,908,102 and 5,921,370 which also dislcose insertscontaining rollers for cooling bed plate transfer grids. My prior U.S.Pat. No. 5,908,102 also discloses that the insert is invertible to allowunworn portions of the bearings to experience axle contact whereby thebearing life is increased. See also my PCT application PCT/US97/24259.

It is also considered desirable to have the ability to install theinserts in a grid at a remote location (insert supplier's businesslocation) where suitably skilled workers are available to allow thecooling bed operator to make the changeover more quickly andinexpensively and without the need on site for people skilled in insertinstallation.

The inserts disclosed in my aforesaid patents have worked well. However,it is considered desirable to provide a less expensive structure formounting rollers to the grid which is also easy to install and whichallows the roller width to be increased to nearly the distance betweenlongitudinal grid members for increased capacity.

The question was raised by a customer whether axles for the rollerscould be rotatable in bearing blocks which are received in cutouts inthe upper edges of grid members.

U.S. Pat. No. 2,593,089 discloses a conveyor having structural sidemembers having upper edges and between which conveyor rollers aremounted. A bearing allows rotation of each roller on a shaft. The endsof the shaft are received in grooves in the upper edges of retainingstrips, which are then slidably engaged in grooves thereby covering thegrooves with the shaft ends therein. In an alternative embodiment, eachend of the shaft has a bearing which is described, in a teaching awayfrom the present invention, as “pressed into hole 3a instead of a slotin retaining strip 4a.” Such a structure does not allow easyinstallation.

My PCT application PCT/US99/00932 (International Publication no. WO99/36277, published Jul. 22, 1999) discloses an axle mounting assemblyfor a vehicle wherein a U-shaped member or yoke defines a verticalupwardly opening slot for receiving an axle, and a block closes theopening to the slot. A wheel is rotatably mounted on the axle.

Other patents which may be of interest are U.S. Pat. Nos. 3,509,978 and5,472,179.

A data sheet (no. 76.26-01.012, dated 1988) of Glacier GMBH—Deva Werkediscloses the use of Deva metal plain bearings for rollers in a coolingbed for sheet steel in a French rolling mill. The pictures and drawingshown thereon appear to show the bearing between the roller and shaftand the shaft ends thus rigidly received in apertures in a respectivepair of adjacent elongate members constituting the bed. Again, such aconstruction would not allow easy installation. In addition, bearingsmounted between the roller and shaft wear out faster and are moresubject to catastrophic damage when worn than if they were placed at theaxle ends.

Accordingly, it is an object of the present invention to provide aninexpensive and easy to install yet reliable structure for securing incutouts in the upper edges of parallel members of a cooling bed platetransfer grid a pair of bearings disposed in the cutouts for an axle fora roller to be received between the parallel members.

It is still another object of the present invention to be able to allowinstallation of the rollers in a grid at a remote location.

It is yet another object of the present invention to double or otherwisesignificantly increase bearing life for great savings to the customer.

It is another object of the present invention to be able to quickly andeasily adjust the roller height, including returning the roller heightto a desired height to compensate for the effects of wear over time.

In order to secure the bearings in the cutouts, in accordance with thepresent invention, a bearing is clamped in a cut-out by means of a platewhich is received in a pair of slots in forward and aft edges of thecut-out to clampingly overlie the bearing.

Also in accordance with the present invention, means are provided forpreventing movement laterally of each bearing, the lateral movementpreventing means preferably comprising a lip on the respective bearingwhich is positioned and sized to abut a lateral surface of a respectivegrid member and a shoulder on the axle which engages the respectivebearing.

In order to double or otherwise significantly increase bearing life forgreat savings to the customer, the bearing blocks are formed to besymmetrical from top to bottom so as to be invertible.

In order to quickly and easily adjust the roller height, the center ofthe bearing block aperture (which receives the axle) is offset from thecenter of the bearing block.

The above and other objects, features, and advantages of the presentinvention will be apparent in the following detailed description of thepreferred embodiment thereof when rad in conjunction with theaccompanying drawings wherein the same reference numerals denote thesame or similar parts throughout the several views.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a portion of a plate transfer grid whichembodies the present invention.

FIG. 2 is a detail partial sectional view thereof taken along lines 2—2of FIG. 1.

FIG. 3 is a plan view thereof with rollers mounted thereto.

FIG. 4 is a perspective view of one of the rollers.

FIG. 5 is a detail partial side view taken along lines 5—5 of FIG. 3.

FIG. 6 is a sectional view of one of the rollers taken along lines 6—6of FIG. 5.

FIG. 7 is an enlarged fragmentary plan view of a pair of adjacentmembers of the grid.

FIG. 8 is a diagrammatic view of a bearing block and axle for one of therollers and illustrating offset of the center of the bearing blockaperture (which receives the axle) from the center of the bearing block.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, there is illustrated generally at 10 a gridwhich, with a plurality of like grids, forms a cooling bed fortransferring hot ferrous and non-ferrous metal plates and for coolingthem by air circulation and the passage of time as they are movedtherealong such as by chains or the like. The transfer grid 10 is castor fabricated as a weldment or otherwise suitably constructed in asingle piece of iron or other suitable material and includes a pluralityof first parallel portions or members 14 extending in the direction oftravel of the plates and providing upper edges or surfaces 16 which,without the rollers described hereinafter, frictionally engage the metalplates for sliding movement of the metal plates there along. The members14 are supportedly joined by cross-portions or cross-members 18 whichextend at right angles thereto. The members 14 project above thecross-members 18 a distance (when members 14 are unworn) of perhapsabout ½ inch to provide the supporting surfaces 16 receiving the platesand along which the plates are conveyed from left to right, as seen inFIGS. 1, 2, and 3. The transfer grid 10 as so far described is of a typewhich is conventional in the art and is described in greater detail inmy aforesaid patents. The transfer grid 10 and other like grids, whichare side-by-side and in end-to-end relation therewith respectively, aresupported by steel beams (not shown) or other suitable supports.

The frictional sliding movement of the metal plates over the surfaces 16of the members 14 causes wear thereof with the result that frequentreplacement of the entire grid has been typically required at high cost.In addition, the under surface of the plates may undesirably be marredas they are conveyed along the grid members 14. In order to reduce suchwear and marring, a plurality of rollers 20 (with rounded corners) aremounted in the grid 10, as described hereinafter, for engaging the hotmetal plates, such as formed in a plate mill, as they are moved alongthe grid. The quantity of inserts installed in a grid may vary accordingto the application or the position of the grid on the cooling bed.

Each roller 20 has an axle 22 which, desirably, is integral therewith(i.e., the roller 20 and axle are desirably a single piece but may ifdesired be separate pieces with the roller fixedly attached to theaxle), and each end of the axle 22 is received in a bearing block, i.e.,a roller, sleeve, or ball bearing 26 or other suitable bearing receivedin a housing 24 (or other suitable bearing means) to allow rotation ofthe axle 22. A bearing is provided at each end of the axle (instead ofbetween the roller and the axle) to provide reduced wear for longerbearing life and a lesser chance of catastrophic damage when worn.

The axle 22 comprises at each end an axially outer portion 23 which isreceived in and engaged by the bearing 26 for rotation of the axle 22and thus the roller 20 and an axially inner enlarged portion 25 joiningportion 23 to the roller 20 and defining a shoulder 27. The bearingblock housing 24 has an increased inner diameter axially inner portion29 defining a shoulder 31. Shoulders 31 engage shoulders 27 respectivelyto limit axial movement of the roller 20 relative to the bearing blockhousings 24.

A pair of cut-outs, illustrated at 28, are machined or otherwisesuitably formed in the upper edges of a pair of adjacent ones of themembers 16 and shaped to receive the bearing blocks 24 for each roller20 with the bearing blocks 24 resting on the bottoms of the respectivecutouts 28 and lying below the upper edges 16 for reasons which willbecome apparent. As seen in FIG. 3, this structure also advantageouslyallows the rollers 20 to be almost as wide as the distance between theadjacent members 14 so as to maximize their capacity for handling heavyplates as well as to minimize the number of rollers required. Moreover,since the rollers need not be height adjusted but merely secured inposition, such a construction also advantageously allows the rollers 20to be installed in a grid at a remote location by workers unskilled inroller installation. The cutouts 28 have radiused bottom corners toreduce stress concentration areas in the grids. The bearing blocks 24are fitted suitably (snugly) into the cutouts 28 so as to maintainmaximum grid strength, i.e., the cutouts 28 are shaped similarly as thebearing blocks so as to snugly receive the bearing blocks 24. While thebearing blocks 24 (as well as the cutouts 28) are shown to berectangular (with radiused bottom corners) shaped, they may otherwise besuitably shaped.

The cutouts 28 and rollers 20 are sized so that the rollers 20 projectabove the upper edges 16 a distance, illustrated at 30 in FIG. 5, of,for example, about ¼ inch.

In order to clamp each of the bearing blocks 24 to its respective member14, in accordance with the present invention, a pair of slots,illustrated at 32, are machined or otherwise suitably formed in theforward and aft edges, 34 and 36 respectively, of each cutout 28 and theend portions of a rectangular or otherwise suitably shaped plate 38inserted in the slots 32 respectively so that the plate 38 extendsacross the cutout 28 to overlie the bearing block with the bearing blockreceived and held between the bottom of the cutout and the plate 38. Thebearing block 24 may alternatively be clamped to the grid by, forexample, use of various kinds of brackets, without the use of the slots32.

In order to retain the plate 38 in the slots 32 so that it does not sliplaterally, the plate is attached to the bearing block 24 by a pair ofscrews 42 or by other suitable means. Each screw 42 is received in anaperture in the plate 38 and threadedly received in a threaded aperturein the bearing block housing 24. In order to prevent loosening of eachscrew 42, a spring pin 44 is suitably inserted in a threaded aperture inthe plate 38, after the screw 42 has been tightened, to abut one of thehex faces of the screw head to prevent it from turning.

If desired, an assembly comprising a stationary (non-rotatable) axle anda roller mounted to the axle by means of a bearing may be mounted in andsecured to the grid 10. Thus, for example, the stationary axle endportion may be fixedly attached to a housing or block having a shapesimilar to that of bearing block 24 so that it may be clamped within thecutout 28 by means of clamping plate 38.

Hotter plates, which are softer, require greater support by the rollersto prevent the rollers from marring the plates. Thus, an increasedroller footprint can handle hotter plates without such marring. Bythusly decreasing the spacing between the roller and the bearing blocks,the likelihood of bearing contamination is also reduced. In order toallow close tolerances between the roller and the grid members 14 (toachieve such a greater footprint) without binding or jamming of theroller against one of the grid members, in accordance with the presentinvention, means are provided for preventing movement axially of theroller 20. Accordingly, each bearing block portion 29 has an increasedouter diameter to define a lip or detent 40 on the axially inner sidethereof, the lip diameter being greater than the width of the cutout 28(or the lip otherwise suitably positioned and shaped) so that the lip 40may abut the grid member 14 and therefore be restrained from passingthrough the cutout 28. The spacing, illustrated at 50, between the lip40 and the respective plate 38 (to allow each of assembly and to preventbinding) is, for example, about {fraction (1/16)} inch. Thus, theclamping plate 38 is held to the bearing block housing 24 by the screws42 and spring pins 44. The combination of the plate and bearing block isrestrained from axial movement in one direction (axially outwardly) bythe lips 40 and in the other direction (axially inwardly) by theshoulders 27. The roller 20 is in turn restrained from movement axiallyby the bearing block shoulders 31. Thus, the entire roller assembly isrestrained from movement axially so that the bearing blocks do notbecome displaced from the cutouts, and axial thrust is handled by theshoulders 27 so that roller position is advantageously maintained. Othersuitable means such as, for example, a tongue and groove or doweledconnection or locking shape between the bearing block 24 and grid mayalternatively be provided to restrain such axial movement.

The following exemplary dimensions and specifications are for thepurposes of illustration and not for purposes of limitation. Forexample, a grid may have a length of about 94¼ inches, a width of about32 inches, have about 7 members 14 and about 7 support members 16 allequally spaced and having a thickness of about 1 inch, and have about 9rollers installed therein. Each cutout 28 may have a width of about 3.01inch, and the distance between the bottom of the cutout and the slots 32may be about 3.06 inches. Each of the slots 32 may extend a distance ofabout 0.44 inch into the edge of the member 14 and have a height ofabout 0.44 inch, and the plate 38 sized accordingly to have a snug fit.The members 14 are machined to control widths of the cutouts 28, asillustrated in FIGS. 1, 2, and 7, in order to provide a precise widthfor seating of the bearing block 24, thus allowing lip 40 to bearagainst or abut machined inner surface 41 of member 14 so that an evencloser tolerance between the roller and members 14 may be obtained. Thebottom corners 43 of the cutouts 28 are suitably radiused (for example,to 1 inch radius). The roller 20 is slightly crowned (for example, a 0.3inch radius) and rounded at its side edges. The corners between the axleand the roller are also rounded. The roller and axle and the plates 38may be composed of high heat, shock, and corrosion resistant steel orother suitable material such as steel used for forgings and whichretains its hardness to temperatures above 1000 degrees F. The bearingblocks may comprise, for example, high temperature heat treatedlubricant transfer type bushings.

In order to quickly and easily and without specialized skill mount andsecure a roller 20 in the grid, the bearing blocks 24, with the roller20 and axle 22 assembled therewith, are inserted in the respectivecutouts 28 with the lips 40 adjacent or abutting the surfaces 41 ofmembers 14 respectively. The clamping plates 38 are then inserted in theslots 32 to overlie the bearing blocks 24 respectively, the screws 42inserted and snugged to a torque of, for example, about 2 to 4 ft. lbs.,and the spring pins 44 inserted and appropriately tightened. In additionto being quickly and easily securable in the cutouts, withoutspecialized skill, the roller assembly according to the presentinvention may be made inexpensively to have a maximum roller width formaximum capacity for handling heavy plates.

In order to increase the bearing block life by as much as double forgreat savings to the customer, the bearing blocks 24 are constructed tobe symmetrical from top to bottom, as best seen in FIG. 4, such thatthey may be inverted after the bottom portions (those portions exposedto wear) have experienced wear or material removal so as to be worn,whereby the unworn upper portion becomes the bottom portion and carriesthe load until it also becomes worn.

In order to quickly and easily adjust the roller height, for example, tocompensate for the effects of wear so as to maintain the desired rollerheight 30, the bearing block 24 is a regular polygon (in a plane normalto the axle 22, as illustrated in FIG. 8) or otherwise suitablysymmetrically shaped to allow it to be removed from the respectivecut-out 28, rotated, and re-inserted therein, and the center of thebearing block aperture (for receiving the axle) is offset from thecenter of the bearing block. Referring to FIG. 8, the bearing block 24is preferably square (and may, whether square or rectangular or havingmore than 4 sides, have rounded corners as illustrated at 70) so as toincrease the height adjustment capability (over a non-square rectangularblock) as described hereinafter. The center of the bearing block 24(geometrically, in a plane normal to the axle, as illustrated) isillustrated at 60. As illustrated in FIG. 8, the center (geometrically,in a plane normal to the axle, as illustrated), illustrated at 62, ofthe aperture, illustrated at 64, for receiving the bearing 26 is offsetfrom the bearing block center 60 in the horizontal direction (as seen inFIG. 8) a distance illustrated at 68. These distances 66 and 68 may, forexample, be about 3 mm and 1 mm respectively, which allows the rollerheight 30 to be adjusted in increments of 2 mm over a total adjustmentof about 6 mm by removing the bearing block 24, rotating it 90 or 180 or270 degrees, and reinserting it, for a total of 4 different heightadjustments. The bearing blocks for both ends of the axle shouldnormally be similarly shaped and normally have similarly offsettingapertures. Thus, by rotating the bearing block 24 counter-clockwise 90,180, and 270 degrees, the roller is respectively raised 4 mm, raised 2mm, and lowered 2 mm from the position shown.

It should be understood that, while the present invention has beendescribed in detail herein, the invention can be embodied otherwisewithout departing from the principles thereof, and such otherembodiments are meant to come within the scope of the present inventionas defined by the claims.

What is claimed is:
 1. A cooling bed plate transfer grid comprising a plurality of elongate parallel members having upper edges respectively for effecting movement of plates being cooled, at least one roller, an axle for said roller, a pair of blocks for receiving ends respectively of said axle, a pair of cutouts in said upper edges of a pair of said parallel members for receiving said blocks respectively with said roller received between and projecting above said parallel members for engaging the plates as they are moved along the grid, each of said cutouts having forward and aft edges, a plate for clamping each of said blocks in said respective cutout, and a pair of slots in said forward and aft edges respectively for receiving said clamping plate with said respective block clampingly received below said clamping plate.
 2. A grid according to claim 1 further comprising a bearing in each of said blocks in which said axle is rotatably received.
 3. A grid according to claim 1 further comprising means for preventing movement axially of said roller.
 4. A grid according to claim 3 wherein said axial movement preventing means comprises a lip on each of said blocks, said lip positioned and sized to abut a lateral surface of said respective parallel member, and further comprises a shoulder on said axle for engaging each said block whereby said blocks are restrained from movement axially in one direction by said lips abutting lateral surfaces respectively of said parallel members respectively and in the other direction by said shoulders and whereby said roller is restrained from movement axially relative to said blocks.
 5. A grid according to claim 4 further comprising means for attaching said clamping plate to said block.
 6. A grid according to claim 5 wherein said attaching means comprises at least one screw and means for preventing loosening of said screw.
 7. A grid according to claim 1 further comprising means for attaching said clamping plate to said block.
 8. A grid according to claim 7 wherein said attaching means comprises at least one screw and means for preventing loosening of said screw.
 9. A grid according to claim 8 wherein said loosening preventing means comprises a spring pin.
 10. A cooling bed plate transfer grid comprising a plurality of elongate parallel members having upper edges respectively for effecting movement of plates being cooled, at least one roller, an axle for said roller, a pair of blocks for receiving ends respectively of said axle, a pair of cutouts in said upper edges of a pair of said parallel members for receiving said blocks respectively with said roller received between and projecting above said parallel members for engaging the plates as they move along the grid, a clamp for clamping each of said blocks in said respective cutout, and means for preventing axial movement of said roller.
 11. A grid according to claim 10 further comprising a bearing in each said block for rotatably receiving said axle.
 12. A grid according to claim 10 wherein said axial movement preventing means comprises a lip on each of said blocks, said lip positioned and sized to abut a lateral surface of said respective parallel member, and further comprises a shoulder on said axle for engaging said respective block whereby said respective block is restrained from movement axially in one direction by said lips abutting lateral surfaces respectively of said parallel members respectively and in the other direction by said shoulder and whereby said roller is restrained from movement axially relative to said blocks.
 13. A cooling bed plate transfer grid comprising a plurality of elongate parallel members having upper edges respectively for effecting movement of plates being cooled, at least one pair of cutouts, each having forward and aft edges, in said upper edges of a pair of said parallel members for receiving end portions respectively of an axle for a roller to be received between and to project above said pair of parallel members for engaging the plates as the plates move along the grid, means for clamping an axle end portion in each of said cutouts, said clamping means comprising slots in said forward and aft edges respectively for receiving a plate with a respective axle end portion received below the clamping plate.
 14. Apparatus comprising a plurality of elongate parallel members having upper edges respectively, at least one roller, an axle for said roller, a pair of blocks for receiving ends respectively of said axle, a pair of cutouts, each having forward and aft edges, in said upper edges of a pair of said parallel members for receiving said blocks respectively with said roller received between and projecting above said parallel members, and a clamp for clamping each of said blocks in said respective cutout, said clamp comprising a plate and further comprising a pair of slots in said forward and aft edges respectively for receiving said clamping plate with said respective block received below said clamping plate.
 15. Apparatus according to claim 14 further comprising a bearing in each of said blocks in which said axle is rotatably received.
 16. Apparatus according to claim 15 wherein said bearing is formed to be invertible so that a top and a bottom thereof may be interchanged.
 17. Apparatus according to claim 14 further comprising means for preventing movement axially of said blocks.
 18. Apparatus according to claim 17 wherein said axial movement preventing means comprises a lip on each of said blocks, said lip positioned and sized to abut a lateral surface of said respective parallel member, and further comprises a shoulder on said axle for engaging each said block whereby said blocks are restrained from movement axially in one direction by said lips abutting lateral surfaces respectively of said parallel members respectively and in the other direction by said shoulders and whereby said roller is restrained from movement axially relative to said blocks.
 19. Apparatus according to claim 14 further comprising means for attaching said clamping plate to said block.
 20. Apparatus according to claim 19 wherein said attaching means comprises at least one screw and means for preventing loosening of said screw. 